Even though I reblogged that post (twice), I do actually disagree with one thing: Dave besting Killian with the lighter had nothing to do with showing him up in regards to his disability. If anything, having a steel hook for a hand would be a help (and not a hindrance) in lighting a fire with flint and steel.
It wasn’t Dave’s two hands that showed Killian up in that instance. It was the modern convenience of a lighter. Dave opening the door the way he did definitely highlighted Killian’s disadvantages having only one hand, but Dave lighting the torch highlighted his disadvantages as a man from a bygone era.
Ultimately, both things ARE seen (by Killian) as demonstrating his unfitness as a romantic partner for a strong, independent, modern lady like Emma... but for two very different reasons.